---
title: "16K RAM Inside the ZX81"
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published_at: "2026-01-16T19:51:45+00:00"
modified_at: "2026-01-16T19:51:46+00:00"
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excerpt: "This article is adapted from one written by John Bell which appeared in the November 1987 issue of L.I.S.T. It applies most directly to readers who have the ZX81, TS1000, or the PC8300. The last mentioned computer is a somewhat modified copy of the Sinclair computers and has a very similar internal layout."
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pubdate: "June 1990"
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---

# 16K RAM Inside the ZX81

This article is adapted from one written by John Bell which appeared in the November 1987 issue of L.I.S.T. It applies most directly to readers who have the ZX81, TS1000, or the PC8300. The last mentioned computer is a somewhat modified copy of the Sinclair computers and has a very similar internal layout.